Rapid development of the mobile internet and a continuous increase in a quantity of network users impose an increasingly higher requirement on a capacity of a wireless network. There are two conventional manners for improving a network capacity: A first manner is adding a new site, and a second manner is adding a system spectrum to extend a carrier frequency. However, due to difficulty in obtaining a site, high costs for deploying a new site, and a limited quantity of wireless spectrum resources, it is difficult to rapidly improve the network capacity in the two conventional manners.
Currently, a sector splitting technology is a cost-effective technical solution for improving the network capacity without adding a new site or a system spectrum. In the sector splitting technology, a sector cell requiring a relatively high network capacity is split into two sector cells; each of the two sector cells obtained by splitting is planned as a cell, where each sector cell uses a cell identifier; and a resource is reused for the two sector cells obtained by splitting, so as to improve a network capacity. However, compared with the original sector cell, an area of each sector cell obtained by using the sector splitting technology is decreased, that is, a coverage area of the cell is decreased, a quantity of cells is increased, and inter-cell interference is severer. This affects network performance such as handover and access, and makes network planning and optimization more complex.
To overcome a problem of the severer inter-cell interference caused by the sector splitting technology, a co-cell networking technology may be applied to the two sector cells obtained by using the sector splitting technology. The co-cell networking technology is combining two sector cells obtained by using the sector splitting technology to form a co-cell network, where the two sector cells in the same co-cell network share a cell identifier. In this way, a network capacity is improved by using the sector splitting technology, network performance such as handover and access is not affected, and complexity of network planning and optimization is reduced. The co-cell networking technology may also be applied to two sector cells that have not been processed by using the sector splitting technology. The two sector cells that have not been processed by using the sector splitting technology are combined to form a co-cell network, and the two sector cells in same the co-cell network share a cell identifier.
A virtual 6-sector cell is used as an example. A conventional 3-sector cell is shown in FIG. 1 (a). Sector cells shown in FIG. 1 (b) are obtained after each sector cell in FIG. 1 (a) is processed by using the sector splitting technology. For example, a cell 0 is split into two sector cells after cell splitting, and the two sector cells share a cell identifier of the cell 0.
In the co-cell network, a base station sends common pilot signals together and sends user data independently. Therefore, a channel mismatch problem exists, and a system throughput is affected.